The impact of arbuscular mycorrhizal fungal communities on drought tolerance of a native Kenyan grass

Background/Question/Methods: Arbuscular mycorrhizal fungi (AMF) alter plant-water relations often increasing plant tolerance to drought. We examined the effects of two arbuscular mycorrhizal fungal communities on drought tolerance of a native Kenyan grass, Themeda triandra. We inoculated plants with fungi from on and off-termite mounds. These areas experience identical climatic conditions but have very different edaphic conditions that alter the way in which fungi and their plant partners experience drought. 

Results/Conclusions: We found that AMF infected drought stressed plants added more leaves post-drought and had more aboveground and belowground biomass than non-AMF drought stressed plants. However, the magnitude of this effect was dependent on the AMF community. Drought stressed grasses inoculated with AMF from termite mounds had 60% more leaves than grasses inoculated with AMF from off-mound areas and more than twice as many leaves as non-AMF control grasses. These findings highlight the important ecological role that AMF play in mitigating drought stress and indicate that different mycorrhizal communities can offer different degrees of physiological advantage.